The present disclosure relates to an illumination device provided with plural kinds of light sources that emit light beams having different wavelengths, and to a display unit which performs picture displaying using the illumination device.
An optical module, which is one of major components in a projector (or a “projection display unit”), is generally structured by an illumination optical system (or an “illumination device”) which includes a light source, and a projection optical system (or an “image projecting optical system”) which includes a light modulation device. In recent years, a small-sized (a palm-sized) and light-weighted portable projector often referred to as a microprojector has gradually been in widespread use in a field of the projector. The currently-available microprojector mainly uses light-emitting diodes (LEDs) for the light source of the illumination device.
On the other hand, much attention has been focused nowadays on the use of a laser as a new light source for the illumination device. For example, a projector utilizing a gas laser has been known as a projector which uses laser beams of three primary colors of red (R), green (G), and blue (B). The projector which uses the laser for the light source has been proposed, for example, in each of International Application Publication No. 2007/116935, Japanese Unexamined Patent Application Publication No. 2009-288520, and Japanese Unexamined Patent Application Publication No. 2010-32797, for example. The use of the laser for the light source makes it possible to achieve a projector having a wider range of color reproducibility and lower power consumption.